Single Crystals of Naturally Occurring Gas Hydrates:The Structures of Methane and Mixed Hydrocarbon Hydrates

摘要

Natural gas hydrates are clathrate inclusion compounds of water and hydrocarbons plus small amounts of other gases,such as CO2 or H2S,with the guest molecules trapped in individual cages in the hydrate crystal lattices.Their role in the geosphere is still under investigation,with potential impact on the global energy supply,geohazards,and global climate change.Three structural families are known,sI,sII,and sH,with the structure determined mainly by the largest guest molecules present.